'52 I. IJLAIA. 



for the ditch-water, as I' have already said, does not form the usual 

 drink of tlie natives. A number of patients whom I saw assured me of 

 never having drank the ditch-water. I do not mean however to exclude 

 all chances of infection directly from tlie water. Secondly, they may 

 be taken in together with the host in which the Cercariœ have developed. 

 In this case the Distoma Avould have but one intermediate host. In 

 this connection I should mention that Paludina and Corbicula are 

 eaten but never in a raw condition. Oysters are abundantly cultivated 

 in the neighborhood, but they are clearly above suspicion since most of 

 them are sent to markets in Okayama where the Distoma-discase is 

 unknown. Thirdly, they may be eaten together with vegetables in an 

 encysted condition after the manner of Distoma hepaticum. I did not 

 observe any edible plants in the ditch, but the fact that the ditch-water 

 is often used for watering vegetable-farms must not be forgotten. 

 Fourthly, they may enter the human body together with the second 

 intermediate host. In this respect shrimps and small miscellaneous 

 fishes as well as molluscs fall under suspicion. Eels and Carassius 

 vulgaris are sent to Okayama markets and are probably harmless. If 

 the words of villagers are to be trusted, symptoms of the Distoma- 

 disease generally manifest themselves late in Snmmcr or at the begin- 

 ning of Autumn. This is suggestive of the fact that the immigration 

 of young Distoma-broods takes place about that time. In the case of 

 sheep-rot, it is known that symptoms appear in the interval from July 

 to September in consequence of the immigration of young Dist. hepati- 

 cum, which attains maturity in 2 — 4 months. 



With these remarks I proceed to give the description of the mature 

 worm. 



In the fresh state the worm is translucent, colorless or with a slight 

 reddish shade. The dark-colored uterus is very conspicuous and other 

 organs such as the testes, the seminal receptacle, the vas deferens, the 



